Substituted nitroimidazolyl-thiadiazoles as growth promoting agents

ABSTRACT

THE USE OF SUBSTITUTED NITROIMIDAZOLYL-THIADIAZOLES AND OXADIAZOLES ARE DESCRIBED ALONG WITH METHODS OF ADMINISTRATION OF THE SAME. THESE COMPOUNDS ARE ACTIVE IN ENHANCING THE GROWTH RATE OF WARM-BLOODED ANIMALS AND IN CONTROLLING THE GROWTH OF PATHOGENIC MICROORGANISMS SUCH AS BACTERIA.

3,830,924 SUBSTITUTED NITROIMIDAZOLYL THIADI- AZOLES AS GROWTH PROMOTING AGENTS Gerald Berkelhammer, Princeton, and Goro Asato, Titusville, N.J., assignors to American Cyanamid Company, Stamford, Conn.

No Drawing. Continuation-impart of abandoned application Ser. No. 17,977, Mar. 9, 1970, which is a continuation of abandoned application Ser. No. 814,205, Apr. 7, 1969, which is a continuation-impart of application Ser. No. 659,596, Aug. 10, 1967, now Patent No. 3,452,035, which is a continuation-in-part of Ser. No. 604,158, Dec. 23, 1966, now abandoned. This application Nov. 15, 1971, Ser. No. 199,005

Int. Cl. A61k 27/00 US. Cl. 424-270 3 Claims ABSTRACT OF THE DISCLOSURE The use of substituted nitroimidazolyl-thiadiazoles and oxadiazoles are described along with methods of administration of the same. These compounds are active in enhancing the growth rate of warm-blooded animals and in controlling the growth of pathogenic microorganisms such as bacteria.

CROSS-REFERENCE TO RELATED APPLICATIONS The present invention is a continuation-in-part of our Application Ser. No. 17,977, filed Mar. 9, 1970, now abandoned, which is a continuation-in-part of our Application 561. No. 814,205, filed Apr. 7, 1969, now abandoned, which is a continuation-in-part of our Application Ser. No. 659,596, filed Aug. 10, 1967, now US. Pat. 3,452,035, which in turn is a continuation-in-part of our Application Ser. No. 604,158, filed Dec. 23, 1966, now abandoned.

BACKGROUND OF THE INVENTION The present invention describes the use and method of administration of compounds which are both highly effective at relatively low concentrations against a broad spectrum of microorganisms, and additionally provide a relatively satisfactory margin of safety. The compositions containing substituted imidazolyl compounds of the present invention are at least 5 to times more active than certain distantly related imidazolyl compounds of the prior art, providing effectiveness at relatively low concentrations, as well as satisfactory margins of safety.

Imidazolyl compounds, in which the heterocyclic rings are joined by a methyleneamine bridge, have been prepared and found to have some antibacterial activity; however, such compound have not been entirely satisfactory for these purposes. The concentration at which such compounds are active is generally much higher than the desirable level; therefore, said compounds do not provide a satisfactory margin of safety. Illustrative of said compounds which have been prepared and found to have such activity are, for example, 3-[(l-methyl-5-nitro-2- imidazolylmethylene)amino] -2-oxazolidinone and 1-[ lmethyl-S-nitro-Z-imidazolylmethylene)amino]-2 imidazolidinone.

SUMMARY OF THE INVENTION The subject matter of the present invention relates to compositions containing as the active component 1-substi tuted-S-nitro-2-imidazolyl compounds and an edible carrier. More particularly, the invention relates to composinited States Patent 0 3,830,924 Patented Aug. 20, 1974 ice tions containing compounds having the following general formula:

-'N NN oml M LIFT-R1 wherein R is selected from the group consisting of lower alkyl, hydroxy lower alkyl, lower alkanoyloxy lower alkyl and benzyl; X is selected from the group consisting of oxygen and sulfur; and R and R are selected from the group consisting of hydrogen, alkyl of 1 to 8 carbon atoms, hydroxy lower alkyl, lower alkoxy lower alkyl, cyclohexyl, formyl, lower alkanoyl, monochlorolower alkanoyl, dichlorolower alkanoyl, morpholino lower a1- kanoyl, lower alkyl aminolower al kyl;

taken together is selected from the group consisting of -N=CHN (lower alkyl) piperazine, N-lower alkylpiperazine, -hydroxy lower alkylpiperazine, N-pyridylpiperazine, N-thiazolylpiperazine, N-lower al'koxycarbonyl piperazine, piperidino and dilower alkylamino lower alkylpiperidino; and physiologically acceptable salts thereof. These salts can be, for example, the hydrochloride hydrobromide, hydroiodide, sulfate, phosphate, etc. The term lower alkyl as employed in the instant specification and claims is intended to include either straight or branched chain having from 1 to 4 carbon atoms. The invention relations to a method of controlling the growth of bacteria in a warm-blooded animal host which comprises administering to the animal therapeutically effective quantitles of the above compounds and thereby alleviating diseases, as well as compositions of matter comprising said compounds and an edible carrier. in addition, methods are described employing the above compounds to promote the growth rate in warm-blooded animals.

Preparation of the Substituted Imidazolyls of the Present Invention In many instances the substituted imidazolyl compounds comprising the active component of the present compositions are prepared by oxidative cyclization of various thiosemicarbazones and semicarbazones of 1-substituted-S-nitro-Z-imidazolecarboxaldehyde. Suitable oxidizing agents for such cyclization of the thiosemicarbazone to aminothiadiazoles include a wide variety of ferric salts such as ferric ammonium sulfate, ferric chloride, ferric nitrate, ferric acetate, sodium ferricyanide, sodium ferric oxalate, potassium ferric sulfate, and the like. The cyclizations of the semicarbazones to aminooxadiazoles are generally carried out with such agents as sodium hypobromite, sodium hypoiodite, and bromine with sodium acetate. The reactions are generally carried out at an elevated temperature between 50 and 150 C., depending on the particular moiety being prepared.

A number of the 2-(2-substituted amino-S-thiadiazolyl)-1-substituted-S-nitroimidazoles can be prepared by the reaction of 2-(Z-halo-S-thiadiazolyl)-l-substituted-5- nitroimidazoles with the appropriate primary or secondary amines in an organic solvent, either in the presence of excess amine or with the use of other acid acceptors, as for example, aqueous sodium bicarbonate solution, usually at between 25 and C.

In the preparation of active components having the above general formula wherein R represents a hydroxy lower alkyl group, it is often practical to first synthesize the corresponding ester, as for example, a compound of the formula:

N NN H onPEL L J k-R,

wherein R is lower al-kanoyloxy lower alkyl and X and R are as defined hereinabove, and then treat the thus formed ester with a strong mineral acid followed by pH adjustment to above about pH 7, thereby yielding the desired product. In many cases, it is found that the conditions used for cyclization l-(2-lower alkanoyloxy lower alkyl)- -nitro-2-imidazole carboxaldehyde thiosemicarbazones are sufficiently acidic to give rise directly to the 2-(2- amino-5-thiadiazolyl)-l-(hydroxy lower alkyl)-5-nitroimidazoles.

Where it is desired to prepare the 2-(2-formamido-5- thiadiazolyl) 1-substituted-nitroimidazole, or the 2-(2- acylamino or 2-haloacylamino-S-thiadiazolyl)-l-substituted-S-nitroimidazole, it is practical to first synthesize the 2-(2-amino-5-thiadiazolyl)-l-substituted S-nitroimidazole, and then treat the product with formic acid, in the case of the preparation of the 2(2-formamino-S-thiadiazolyl)-lsubstituted-S-nitroimidazole, or with an anhydride of the formula (lower alkanoyl) or (halo lower alkanoyl) or with the appropriate acid chloride in the instance of the preparation of the 2-(2-acylamino or 2-haloacylamino-5- thiadiazolyl) 1-substituted-S-nitroimidazole. Similar reactions can be carried out to give the corresponding oxadiazolyl compounds. These reactions are usually carried out at an elevated temperature, particularly at temperatures between 50 and 150 C.

The 2 (Z-amino-S-thiadiazolyl)-1-lower alkanoyloxy lower alkyl-S-nitroimidazoles and the corresponding oxadiazolyl compounds, active components of the present compositions, can be made by esterifying the 2-(2-amino-5- thiadiazolyl or 5-oxadiazolyl)-l-hydroxy lower alkyl-S- nitroimidazoles by heating with an aliphatic acid in the presence of a mineral acid catalyst. If, instead, an aliphatic acid anhydride is employed, the products are 2- (2-lower alkanoylamino-S-thiadiazolyl or 5-oxadiazolyl)- l-lower alkanoyl lower alkyl-S-nitroimidazoles. In the latter case, a catalyst is usually not necessary. In both instances, reaction temperatures of from 50 to 150 C. are frequently employed.

For the preparation of N,N-dilower alkyl-N-[5-(1-substituted 5 nitro-2-imidazolyl)thiadiazol-2-yl]formamidines, products of the reaction of N,N-dilower alkyl formamides with phosgene, phosphorus oxychloride, or thionyl chloride are reacted with 2-(Z-amino-S-thiadiazolyl)-lsubstituted-S-nitroimidazoles in an organic solvent, as for example, in an excess of the N,N-dilower alkyl formamide, usually at the ambient temperature.

The active components of the compositions of the instant invention are highly effective in controlling infections of pathogenic and other microorganisms such as Escherichia coli, Salmonella gallirzarum, Salmonella ch0- teraesuis var. kzuzzendorf, Proteus mirabilz's, Staphylococcus aureus strain Rose or strain Smith, Salmonella typhosa, Klebsiella AD, Aerobacter acrogenes, Streptococcus pyogenes, Pasteurella multocz'da, etc. Tests showing the use of a compound of this invention against bacteria are described in Antimicrobial Agents and Chemotherapy-- 1968 page 534 etc., in a warm-blooded animal host; said active components may be administered to the warmblooded animals, such as goats, sheep, cattle, hogs, chickens, etc., in admixture with their feed or drinking water. Furthermore, the compositions may be administered .in the form of tablets, pills, capsules or the like, or parenterally by injection either intramuscularly or subcutaneously.

The concentration employed in feed or water may be in the range of from 5 to 1,000 parts per million, preferably 15 to 500 parts per million; the most preferred concentration being about 50 to 200 parts per million. The above compositions have demonstrated effectiveness against Salmonella infections when the active component was administered in as little as 0.025% concentration in the diet of chicks and mice. In addition, some of the active components provide control of Escherichia coli infections in chicks when administered at about 40 mg. per kg. of body weight in a single oral dose and are highly effective against a number of other bacterial infections, both gram-positive and gram-negative.

The active components of this invention can be used with pharmaceutically acceptable edible carriers in compositions such as tablets (containing 1 mg. to 100 mg. per kilogram of body weight), wherein the principal active ingredient is mixed with conventional tableting ingredients such as corn starch, lactose, sucrose, sorbitol, talc, stearic acid, magnesium stearate, dicalcium phosphate, gums, and fractionally similar materials as pharmaceutical diluents or carriers. The tablets or pills of the novel compositions can be laminated or otherwise compounded to provide a dosage form affording the advantage of prolonged or delayed action or predetermined successive action of the enclosed medication. For example, the tablet or pill can comprise an inner dosage and an outer dosage component, the latter being in the form of an envelope over the former. The two components can be separated by an enteric layer which serves to resist disintegration in the stomach, and permits the inner component to pass intact into the duodenum or to be delayed in release. A variety of materials can be used for such enteric layers or coatings, such materials including a number of polymeric acids or mixtures of polymeric acids with such materials as shellac, shellac and cetyl acohol, cellulose acetate and the like. A particularly advantageous enteric coating comprises a styrene maleic acid copolymer together with known materials contributing to the enteric properties of the coating. The term dosage form as described herein refers to physically discrete units suitable as unitary dosage for warm-blooded animal subjects, each unit containing a predetermined quantity of active material calculated to produce the desired therapeutic effect in association with the required pharmaceutical diluent, carrier or vehicle. Examples of suitable oral dosage forms in accord with this invention are tablets, capsules, pills, powder packets, granules, wafers, cachets, teaspoonfuls, dropperfuls, ampules, vials, segregated multiples of any of the foregoing and other forms as herein described.

The compounds of this invention have been found to promote the growth rate of warm-blooded animals, such as goats, sheep, cattle, hogs, chickens, etc. Said compounds may be administered in a manner similar to their introduction as antibacterial agents, such as orally or parenterally.

DETAILED DESCRIPTION The following examples are provided for illustrative purposes and may include particular features of the invention; however, the examples should not be construed as limiting the invention, many variations of which are possible without departing from the spirit or scope thereof. Parts are by Weight unless otherwise indicated.

EXAMPLE 1 Preparation of 2-(Z-Amino-S-Thiadiazolyl -l-methyl-5 nitroimidazole A mixture of 4.71 gm., 0.03 mole, of l-methyl-Z-hydroxymethyl-S-nitroimidazole, and 13.3 gm., 0.03 mole, of lead tetraacetate in 200 ml. of benzene, is refluxed while stirring magnetically for about 18 hours, cooled and filtered. The filtrate is washed with 50 ml. of saturated sodium carbonate solution. The organic phase is then separated, and the aqueous phase extracted twice with 30 ml.

of chloroform. The combined organic phase is then dried over magnesium sulfate. After filtering and evaporating the organic phase to dryness, the filtrate gives 4.2 gm. of pale yellow 1-methyl-5-nitro-2-imidazolecarboxaldehyde, which is dissolved in 25 ml. of hot ethanol, then added to 2.5 gm. of thiosemicarbazide in ml. of boiling ethanol containing two drops of concentrated hydrochloric acid. The mixture is then boiled for a few minutes with stirring, cooled and bright yellow crystals of the thiosemicarbazone of the above aldehyde are collected. The process yields 5.3 gm., which constitutes a 77.4% overall yield, said material having a melting point of 227 C. (decomposition).

To ml. of hot water containing 5.7 gm., of ferric ammonium sulfate dodecahydrate, 2.68 gm. of the above thiosemicarbazone is added, and the mixture is stirred magnetically in a boiling water bath. After 1 hour, an additional 75 ml. of hot water containing 17.1 gm. of ferric ammonium sulfate dodecahydrate is added to the above mixture. The mixture is then heated for approximately 3 hours in a boiling water bath, and filtered while still hot, yielding orange brown crystals which are washed thoroughly with hot water. The yield is 2.7 gm., having a melting point of from 259 to 260 C. (decomposition). This product is dissolved in about 20 ml. of hot dimethylformamide, filtered and the warm filtrate poured on ice. The precipitated product is washed thoroughly first with water, and then cold acetone, giving a yellow product which is dried in vacuo at 100 C. for several hours. The purified product weighs 1.55 gm., and has a melting point of from 268 C. (decomposition). The product is then submitted to analysis; calculating from carbon, hydrogen, nitrogen and sulfur, the actual values agreed closely with the theoretical values.

EXAMPLE 2 Preparation of 2-(2-Methylamino-S-thiadiazolyl)-1- methyl-S-nitroimidazole A suspension of 20 gm. of ferric ammonium sulfate dodecahydrate in 100 ml. of water is warmed on a steam bath until the solid is completely dissolved. To the above solution 9.6 gm. 0.039 mole, of l-methyl-5-nitro-2-imid azolecarboxaldehyde-4'-methyl 3' thiosemicarbazone is added, and stirred on the steam bath for an additional 90 minutes. A warm solution containing 59 gm., 0.122 mole of ferric ammonium sulfate dodecahydrate in 300 ml. of water is added to the above mixture. The mixture is stirred on the steam bath for an additional 2 hours and filtered. The precipitate is washed with water and acetone to give 6.9 gm. of a yellow solid having a melting point of from 230 to 238 C. Recrystallization from 700 ml. of hot ethyl acetate gives 3.3 gm. of bright yellow needles having a melting point of 238 C.

EXAMPLE 3 Preparation of 2-(2-Dimethylamino-S-thiadiazolyl)-1- methyl-S-nitroimidazole A mixture of 14.1 gm., 0.1 mole, of 1,2-dimethyl-5- nitroimidazole, 12 gm., 0.1 mole, of selenium dioxide and 100 ml. of diethyleneglycol dimethyl ether is refluxed while stirring magnetically for approximately 4 hours. The mixture is then cooled and filtered through a layer of diatomaceous earth into a warm solution of 11.5 gm., 0.1 mole of 4,4-dimethyl-3'-thiosemicarbazide in 50 ml. of water and 10 ml. of glacial acetic acid. A precipitate forms immediately. The mixture is cooled and filtered to give 7.5 gm. of yellow crystals, which have a melting point of from 205 to 210 C. The crystals are recrystallized twice from methyl Cellosolve and once from ethanol, to give 1.3 gm. of orange needles having a melting point of from 208 to 210 C. (decomposition).

A warm suspension of 9.2 gm. of 1-methyl-5-nitro-2- imidazolecarboxaldehyde 4',4-dimethyl-3'-thiosemicarbazone (prepared above) in ml. of water is added to a warm solution of 69.4 gm. of ferric ammonium sulfate dodecahydrate in 400 ml. of water. The mixture is magnetically stirred on a steam bath for approximately 4 hours, and filtered. The precipitate is washed with water and acetone giving 8.6 gm. of a brown solid having a melting point of from 238 to 240 C. (decomposition). Two recrystallizations from N,N-dimethylformamide gives 3.6 gm. of yellow crystals having a melting point of 252 C.

EXAMPLE 4 Preparation of 2-(2-Ethylamino-5-thiadiazolyl)-1-methyl- 5-nitroimidazole and Z-(Z-Dimethylamino 5 thiadia- Zolyl) -1-ethyl-5-nitroimidazole EXAMPLE 5 Preparation of 2-(2-F0rmamido-S-thiadiazolyl)-1-methyl- 5-nitroimidazole The above compound is prepared by refluxing 8 gm. of 2-(2-amino-5-thiadiazolyl) 1 methyl 5 nitroimidazole in 30 ml. of 98% formic acid for 10 hours, cooling, and adding the mixture to saturated sodium bicarbonate solution, and the solid collected. The compound melts at 225 to 227 C.

EXAMPLE 6 Preparation of 2-(2-Acetamido-5-thiadiazolyl)-l-methyl- 5-nitroimidazole The above compound is prepared by heating under re.- fiux for 30 minutes a mixture of 14 gm. of 2-(2-amino-5- thiadiazolyl)-1-methyl 5 nitroimidazole in 280 ml. of acetic anhydride. The mixture is evaporated to dryness, and the solid residue is washed thoroughly with ether giving 16.4 gm. of a yellow solid having a melting point of 235 C. (decomposition).

EXAMPLE 7 Preparation of 1-(2-Actoxyethyl)-5-nitro-2-imidazole carboxaldehyde A 6.27 gm. portion of 1-(2-acetoxyethyl)-2-hydroxymethyl-S-nitroimidazole is refluxed with 13.3 gm. of lead tetraacetate in 200 ml. of benzene for 18 hours, cooled, and filtered. The filtrate is washed with 50 m1. of saturated sodium carbonate solution, and the organic phase is separated therefrom. The ramining aqueous phase is twice extracted with 30 ml. of chloroform, and then combined with the above separated organic phase. The combined organic phases are dried under magnesium sulfate, and filtered. The organic solvents are then removed in vacuo, giving the above aldehyde.

EXAMPLE 8 Preparation of 2-(2-Amino-5-thiadiazoly1)-1-(2-hydroxyethyl)-5 -nitroimidazo1e A 14.25 g. sample of the aldehyde prepared in Example 7 is treated with 5.72 g. of thiosemicarbazide in ml. of 95% ethanol containing a drop of concentrated hydrochloric acid and the mixture is heated on a steam bath for 20 minutes. The hot solution is filtered to remove insoluble materials, cooled and the yellow-brown crystals are collected. The yield of 1-(2-acetoxyethy1)-5-nitro-2- imidazolecarboxaldehyde thiosemicarbazone is 18.8 g. after drying in a vacuum oven at 60 for 2 /2 hours. Recrystallization of the product gives a yellow solid, melting point 181-183.5 C.

The thiosemicarbazone (12 g.) is added to 77 g. of ferric ammonium sulfate dodecahydrate in 500 ml. of water at 60 and the mixture is heated to 90-100" for 4 hours. The mixture is cooled, the solid collected and washed with water. Only 0.92 g. (melting point 249- 251) of product is soluble in a large volume of acetone. The remaining product is dissolved in 150 ml. of dimethylformamide, filtered and the filtrate evaporated to dryness to give a solid. This solid is treated with about 20 ml. of acetone, slurried, cooled and collected to give yellow crystals. After drying in an air stream overnight, 5.5 g. (melting point 253.5-255) of 2-(2-amino-5-thiadiazolyl) 1-(2-hydroxyethyl)-5-nitroimidazole is obtained; no carbonyl absorption band is present in the infrared spectrum. Thus, it is not necessary to perform a separate hydrolysis step for the removal of the acetyl group.

EXAMPLE 9 Preparation of 2-(2-Dichloroacetamido-S-thiadiaZolyl)- 1-methy1-5-nitroimidazole Five grams of 2-amino-5-(1-methy1-5-nitro-2-imidazolyl)-l,3,4-thiadiazole is added to 25 ml. of dichloroacetic anhyride, and the mixture boiled gently for a few minutes. After standing at room temperature for four hours, 200 ml. of diethyl ether is added, and the mixture stored at 10 C. overnight. The solid is collected, dried, and recrystallized from a mixture of 300 ml. of ethanol and 50 ml. of 2-methoxyethanol to yield 4.5 g. of pure product melting at 246-247 C.

EXAMPLE 10 Preparation of 2-(2-Amino-5-oxadiazolyl)-l-methyl-S- nitroimidazole Method A.In 180 ml. of hot water, 9.3 grams (0.06 mole) of 1 methyl-S-nitro-2-imidazolecarboxaldehyde is slurried while 6.7 grams (0.06 mole) of semicarbazide hydrochloride is added portionwise. After minutes of heating, the mixture is cooled in a refrigerator overnight. The solid is then collected and washed with water and methanol, respectively, to give a yellow product, melting point 272-273 C. (dec.). After drying at 100 for 2 hours under reduced pressure, 11.94 grams of l-methyl-S- nitro 2 imidazolecarboxaldehyde semicarbazone is obtained. This semicarbazone (6.35 grams or 0.03 mole) is added to 10 grams of anhydrous sodium acetate in 50 ml. of glacial acetic acid and 1.25 ml. of bromine is added with continuous stirring. The mixture is heated gradually to give a nearly clear red solution at 50 C. which becomes increasingly turbid with time. After heating at 75 i3 for 3 hours, the mixture is cooled and poured on ice. The yellow solid is collected, washed with water, then with methanol, and dried under reduced pressure at 70 C. for 3 hours to give 5 grams of crude 2-amino-5-(1- methyl 5 nitro-2-imidazolyl)-oxadiazole, melting point 284-287 C. (dec.). This material is dissolved in boiling dimethylformamide, ethanol added, and the mixture cooled to give yellow crystals, melting point 291-293 C. (dec.).

Method B.--In ml. of methanol, 0.93 grams (5 mmole) of 1 methyl-5-nitro-2-imidazolecarboxylic acid hydrazide and 0.53 grams (5 mmole) of cyanogen bromide are refluxed for 2 hours, cooled, and poured on ice to give a pale yellow solid. This solid is collected, washed with water, and dried under reduced pressure at 100 C. for 2 hours to give 0.65 grams, melting point 286-288 C. (dec.), of 2 amino-5-(1-methyl-5-nitro-2-imidazolyl) oxadiazole.

8 EXAMPLE 11 Preparation of 2-(2-Methylamino-5-oxadiazolyl)-1-methyl-5-nitroimidazole To a solution of 8.5 grams (0.055 mole) of 1-methyl- 5-nitro-2-imidazolecarboxaldehyde in 50 ml. of ethanol is added a solution of 5.0 grams (0.056 mole) of 4-methylsemicarbazide in 25 ml. of ethanol and 10 ml. of water containing 24 drops of concentrated hydrochloric acid. The resulting solution is heated at 6070 C. until a yellow solid starts to separate and then stored at 0 C. for 1 hour; 12.2 grams (98%) of I-methyl-S-nitro-Z-imidazolecarboxaldehyde 4 methylsemicarbazone is obtained melting at 221223 C.

Seven grams (0.031 mole) of 1-methyl-5-nitro-2-imidazolecarboxaldehyde-4-methylsemicarbazone is dissolved in ml. of glacial acetic acid, 16 grams of anhydrous sodium acetate added, and a solution of 2.5 ml. of bromine in 20 ml. of glacial acetic acid added. The resulting mixture becomes a clear solution as it is heated at 7080 C. for 2-4 hours. The solvent is evaporated under reduced pressure and the residue treated with shaved ice until a yellow suspension is obtained. The product is collected, washed with cold water, methanol, and finally with ether. Recrystallization from ethanol containing N,N-dimethylformaamide affords 2.7 grams (39%) of a yellow product melt ing at 239-241 C. In another preparation, a 63% yield of product melting at 237239 C. is obtained without recrystallization.

EXAMPLE 12 Preparation of 2-(Z-Dimethylamino-S-oxadizolyl)-1- methyl-S-nitroimidazole A solution of 780 mg. (5 millimoles) of l-methyl-S- nitro-2 imiclazolecarboxaldehyde in 10 ml. of ethanol is treated with 520 mg. (5 millimoles) of 4,4-dimethylsemicarbazide and one drop of concentrated hydrochloric acid to give a yellow solid. The mixture is heated at 40 C. for 5 minutes, cooled to 0 C., and 1180 mg. (98%) of crystalline 1 methyl-S-nitro-Z-imidazolecarboxaldehyde 4,4-dimethylsemicarbazone is obtained. Recrystallization from ethanol containing N,N-dimethylformamide affords 900 mg. (74%) of material melting at 206-208 C.

The procedure of Method A of Example 10 is followed except that 7.5 grams (0.31 mole) of 1-methyl-5-nitro-2- imidazolecarboxaldehyde 4,4-dimethylsemicarbazone, prepared above, is used. The product is recrystallized from ethanol to give 5.2 grams (69%) of material melting at 180-182 C.

EXAMPLE 13 Preparation of 2- Z-Acetarnido-S-oxadiazolyll-methyl- S-nitro-imidazole Four grams of acetyl chloride are slowly added to 3.6 grams (0.017 mole) of 2 (2-amino-5-oxadiazo1yl)-lmethyl-S-nitroimidazole suspended in a mixture of 44 ml. of pyridine and 35 ml. of benzene. The addition is completed in 30 minutes, the mixture heated at 6070 C. for 10 minutes, and then poured into 500 ml. of ice and Water. After the resulting mixture is stirred for 1%: hours, the product separates. Recrystallization from 150 ml. of acetone containing some N,N-dimethylformamide affords 2.4 grams (56%) of pale yellow product. A second recrystallization from acetone gives 2.1 g. of product, melting point 224-225" C.

EXAMPLE 14 Preparation of 2-{2-[ (Dimethylaminomethly'ene) amino]-5-thiadiazoly}-1-methyl-S-nitroimidazole Phosgene gas is bubbled into ml. of N,N-dirnethyl formamide at 5-l0 C. until 2.0 g. (0.02 mole) is absorbed and a crystalline suspension is formed. This suspension is added in portions to a stirred mixture of 4.5

9 g. (0.02 mole) of 2-(2-amino-5-thiadiazolyl) 1 methyl- -nitroimidazole and 100 ml. of N,N-dirnethylformamide at 25 C. After 30 minutes the reaction mixture is diluted with 200 m1. of diethyl ether, and the pale yellow solid is collected, washed with ether, and dried. Treatment of this material with 150 ml. of water and drying afiords 5.0 g. (89%) of brilliant yellow solid melting at 230- 232 C.

' EXAMPLE 15 Preparation of 2-[2-(4-Carbethoxy-1-piperazinyl)-5- thiadiazolyl] l-rnethyl-S-nitroimidazole The compound of 1 methyl 5 nitro-2-imidazole carboxaldehyde 4 carbethoxy-l-piperazine thiocarbohydrazone is prepared by the procedure of Example 3, 23.2 gm., 0.1 mole, of 4-carbethoxypiperazine-1-thiocarbohydrazide replacing the 4,4 dimethyl-3-thiosemicarbazide. The yield is 8.6 gm. and the melting point 182"- 183" C.

A suspension of 6.4 gm., 0.0174 mole, of 1-methy1-5- nitro-2-imidazolecarboxaldehyde-4-carbethoxy 1 piperazine thiocarbohydrazone (prepared above) in 200 ml. of boiling ethanol is stirred as a solution of 35 mg. of ferric ammonium sulfate dodecahydrate in 200 ml. of hot water is added in one portion. A deep red-brown solution results. After stirring and heating on the steam bath for four hours, a precipitate is present. This is collected, washed with water, dried and recrystallized from hot ethanol to give 3.6 grams of the title compound melting at 179181 C.

EXAMPLE 16 Preparation of 2- [2-(Hydroxyethylamino)-5-thiadiazolyl]-1-methyl-5-nitroimidazole A solution of 1.3 gm., 0.0058 mole, of 2-(2-amino-5- thiadiazolyl) 1 methyl-S-nitroimidazole is dissolved in 25 ml. of concentrated hydrochloric acid, cooled to 5 C., stirred, and treated during five minutes with a solution of 0.5 gm., 0.0073 mole, of sodium nitrite in 2 ml. of water. The mixture is kept at room temperature for eighteen hours. The precipitate present is collected, washed with water, dried and then extracted with warm acetone. Removal of the acetone leaves a solid residue which is recrystallized from a mixture of acetone and diethyl-ether to give 0.16 gm. of 2-(2 chloro-S-thiadazolyl) I-methyl-S-nitroimidazole as yellow crystals, melting at 135137 C.

A mixture consisting of 4.9 gm., 0.02 mole, of 2-(2- chloro-S-thiadiazolyl)-1-methyl-5-nitroimidazole, 3.0 gm., 0.05 mole, of ethanolamine, and 50 ml. of p-dioxane is stirred at room temperature for twenty-four hours. The precipitate is collected, washed with aqueous sodium bicarbonate solution, dried and recrystallized from methanol to give the pure compound melting at 208209 C. Working up the mother liquors gives additional material, the total yield being 3.4 gm.

EXAMPLE 17 Preparation of 2- [2- 3-Dimethylaminopropylamino) -5- thiadiazolyl] 1 -methyl-5-nitroimidazole A mixture consisting of 3.8 gm., 0.0155 mole of 2-(2- chloro-5 thiadiazolyl)-l-methyl 5 nitroimidazole, prepared as in Example 16 2.5 gm., 0.029 mole of 3-dimethylarninopropylamine, 2.1 gm. 0.025 mole, of sodium bicarbonate and 100 ml. of benzene is refluxed for twenty-two hours. The reaction mixture is cooled to room temperature, washed with aqueous sodium bicarbonate and sodium chloride solutions. Cooling to 5 C. gives a crystalline precipitate which is collected and recrystallized from benzene to give the pure compound melting at 153 154 C. More product is obtained from the mother liquors to give an overall yield of 3.0 gm.

10 EXAMPLE 1% Preparation of 2-(2-Amino-5-oxadiazolyl)-1-(2-hydroxy ethyl)-5nitroimidazole, 2-(2-methylamino 5 oxadiazolyl -1- (2-hydroxyethyl) -5-nitroimidazole, and 2-( 2- dimethylamino-S-oxadiazolyl)-1-(2 hydroxyethyl)-5- nitroimidazole 1-(2-hydroxy) 5 nitro-2-imidazolecarboxaldehyde (1 mole) is treated with 1 mole of semicarbazide hydro chloride in ethanol to give nearly a quantitative yield of semicarbazone. The product is treated with bromine and sodium acetate in the manner described in'Method A of Example 1 to give the first compound above which melts with decomposition at 228230 C.

The use of 4 methylsemicarbazide and 4,4-dimethylsemicarbazide hydrochlorides instead of semicarbazide hydrochloride, followed by treatment of the methylated semicarbazones with bromine and sodium acetate as above, gives respectively, 2-(2-methylamino 5 oxadiazolyl) 1 (2-hydroxyethyl) 5 nitroimidazole, melting at 202.5 204 C., and 2-(2-dimethlyamino-5- oxadiazolyl )-1-(2-hydroxyethyl)-5-nitroimidazole, melting at 171-173 C.

EXAMPLE 19 Preparation of 2-(2-Amino-5-thiadiazolyl)-1-(2- acetoxyethyl -5 -nitroimidazole The sample (0.1 g.) of 2-amino-5-[1-(2-hydroxyethyl)- 5-nitro-2-imidazolyl]thiadiazole is dissolved in 2 m1. of hot glacial acetic acid and a drop of concentrated sulfuric acid is added. The solution is refluxed for 45 minutes, cooled and poured on ice to give a yellow solid. This solid is collected, washed with water and dried; the yield is 0.1 g., melting point 159-162 C. (turbid). A purified sample of the 2-amino-5-[1-(2-acetoxyethyl)-5-nitro- Z-imidazolyl]thiadiazole, melts at 164l65.5 C.

EXAMPLE 20 Preparation of 2- (2-Acetamido-5-thiadiazolyl) -1-(2- acetoxyethyl) -5 -nitroimidazole The sample (0.1 g.) of 2 amino-5-[1-(2-hydroxyethyD-S-nitro 2 imidazolyl]thiadiazole is added to 1.5 ml. of acetic anhydride and heated under reflux for 20 minutes. After cooling, the mixture is evaporated to dryness to give a tan solid which is slurried with ether and collected, melting point 258-265 C.; the yield is 0.11 g. This solid is recrystallized from acetone to give the purified product, melting point 264268 C.

EXAMPLE 21 Preparation of 2-(2-Amino-5-thiadiazolyl)-1-methyl-5- nitroimidazole hydrochloride Four grams of 2-(2-amino 5 thiadiazolyD-l-methyl- 5-nitroimidazo1e is added to concentrated hydrochloric acid. The resultant precipitate of the hydrochloride is filtered oil and air dried; melting point 249 C. with decomposition. When the hydrochloride is added to water, the free base is formed again without the necessity of using alkali.

EXAMPLE 22 Preparation of 2-(2-Hydroxymethylamino-S-thiadiazolyl)- l-methyl-S-nitroimidazole A suspension of 5 g. of 2-(Z-amino-S-thiadiazolyl)-lmethyl-S-nitroimidazole in 200 ml. of 36% aqueous formaldehyde solution is stirred for 20 hours at room temperature. The suspension is cooled in ice, and the insoluble solid is collected by filtration and washed with acetone. The yield of the title compound is 6.15 g., melting point 177 C. with decomposition (rapid heating).

.1 1 EXAMPLE 23 Preparation of 2-('Z-Amino-S-thiadiazolyl)-1-ethyl- -nitroimidazole A slurry of B-(l-ethyl 5 nitro-2-imidazolyl)styrene (42.7 g. or 0.175 mole) in 350 ml. of methanol containing 14.6 ml. of water at C. is treated with ozone until a nearly clear, pale-yellow solution is obtained. Subsequently, the mixture is treated with 42 g. of sodium iodide in 138 ml. of water and 20.3 ml. of glacial acetic acid at 25 C. The mixture is stirred for minutes and 44.1 g. (0.288 mole) of sodium thiosulfate in 242 ml. of water added. The mixture is filtered, and the filtrate concentrated at 70-75 C. under 1520 mm. of pressure to give 450 ml. of solution. The solution is acidified with ml. of 6N hydrochloric acid and the benzaldehyde removed at -75 C. under 15-20 mm. of pressure. The residue is then neutralized with saturated sodium bicarbonate solution and extracted with ethyl acetate to give an 81.5% yield of solid aldheyde, melting point 61- 67 C. after stripping. A sublimed sample of the aldehyde melts at 68 69 C. with softening at 65 C. When the aqueous ozonized solution, after benzaldehyde is removed, is treated with thiosemicarbazide and mineral acid or semicarbazide hydrochloride and heated, the l-ethyl- 5-nitro 2 imidazolecarboxaldehyde thiosemicarbazone, melting point 241 C., or semicarbazone, melting point 223 226 C., is obtained. The compound fi-(l-ethyl-S- nitro-2-imidazolyl)styrene is prepared by treating l-ethyl- 2-methyl-5-nitroimidazole with benzaldehyde in absolute ethanol and potassium tertiary butoxide in nitrogen atmosphere below 37 C. A sample purified from 95% ethanol melts at 136.5137.5 C.

A solution of 184 g. of ferric ammonium sulfate dodecahydrate in 680 ml. of water is heated to 60 C. and 23.1 g. of 1-ethyl-5-nitro-2-imidazolecarboxaldehyde thiosemicarbazone (prepared as above) is added with efiicient stirring. The temperature is raised to C. and vigorous stirring continued for 4 hours. The reaction mixture is cooled to 4 C. and filtered. The solid is washed with warm water and dried under vacuum at 110 C. and then extracted with 800 ml. of hot acetone, followed by three 300-ml. portions of hot acetone. Cooling the acetone gives a solid product, which is filtered off; melting point 231- 233 C. A second crop with the same melting point is obtained by evaporating the filtrate and recrystallizing the residue from acetone. The combined yield is 17.0 g. (74.5

EXAMPLE 24 Preparation of 2-(2-Amino-5-thiodiazolyl)-l-benzyl- S-nitroimidazole 0.5 g. (1.64 millimole) of fi-(1-benzyl-5-nitro-2-imid azolyl)styrene in aqueous methanol is treated with ozone until a clear solution is obtained. To this solution at 15 C., 0.312 g. (1.64 millimole) of sodium metabisulfite (Na S O in 3 ml. of water is added. The mixture is then evaporated to dryness under reduced pressure at 75 C. and the solid extracted with ethyl acetate. The ethyl acetate extracts are dried, evaporated to dryness to give a yellow-orange residue (probably bsulfite addition product) which solidifies upon standing. This material is dissolved in 20 ml. of aqueous methanol and 0.15 g. of thiosemicarbazide and a drop of 6N hydrochloric are added. After refluxing for 15 minutes and cooling, 0.25 g., melting point 193196 C., of l-benzyl- 5-nitro-2-imidazolecarboxaldehyde thiosemicarbazone is isolated. The use of a half of an equimolar amount of sodium meta-bisulfite affords the title aldehyde instead of the bisulfite addition product. When the ethyl acetate extract is evaporated to dryness and dissolved in 75% aqueous ethanol and semicarbazone is added, and the mixture is heated on a steam bath for 10 minutes, and sodium acetate is added, the semicarbazone derivative, melting point 22.6228 C. is obtained. Twelve grams of 1-ben zyl-5-nitro-2-imidazolecarboxaldehyde thiosemicarbazone are added to a stirred solution of 76.2 g. of ferric ammonium sulfate dodecahydrate in 600 ml. of water at 50 C. and the slurry is heated at 90--95 C. for 6 hours. The mixture is cooled in ice and the yellow-brown solid collected, washed with water, and dried under reduced pressure. The yield of product is 10.9 g. Recrystallization from methanol gives analytically pure material melting at 213 215 C.

EXAMPLE 25 Preparation of 2-(2-Amino-5-oxadiazolyl)-1-ethyl- 5-nitroimidazole A slurry of 10.2 g. of 1-ethyl-5-nitro-2-imidazole carboxaldehyde semicarbazone (prepared as in Example 23), and 15.0 g. of anhydrous sodium acetate in 75 ml. of glacial acetic acid is treated with 1.87 ml. of bromine at 81 C. under agitation. Stirring is continued at 7580 C. for 17 /2 hours, at which time workup of a sample shows starting material still present. An additional 7.5 g. of sodium acetate and 1.00 ml. of bromine are added and stirring continued for 3 hours. A final 3.85 g. of sodium acetate and 0.50 ml. of bromine are added and the reaction mixture is stirred for one hour at 75 C. The reaction mixture is cooled to 15 C. and poured over ice. The product is filtered off, washed with water and dried under reduced pressure. The yield is 6.3 g. and the melting point 265 C. with decomposition.

EXAMPLE 26 Preparation of 2-(2-Arnino-5-oxadiazolyl)-1-benzyl- 5-nitroimidazole A slurry of 6.1 g. of l-benzyl-5-nitro-2-imidazolecarboxaldehyde semicarbazone (prepared as in Example 24) and 8 g. of anhydrous sodium acetate in 40 ml. of glacial acetic acid is stirred at 40 C. while 3.4 g. of bromine in 15 ml. of acetic acid is slowly added. The mixture is heated at 65-70 C. for 4 hours, then poured on ice and the yellow solid collected, washed with water, and dried under reduced pressure. The yield is 5.7 g. Recrystallization from acetone gives analytically pure material melting at 261.5262.5 C.

EXAMPLE 27 Preparation of 2-[2-(2,2-Diethoxyethylamino)-5- thiadiazolyl]-1-methyl-5-nitroimidazole A mixture composed of 9.8 g. of 2-(2-chloro-5-thiadiazolyl)-1-rnethyl-5-nitroimidazole (Example 16), 11.0 g. of 2,2-diethoxyethylamine, and 250 ml. of dioxane is stirred and heated on the steam bath for 12 hours. It is then diluted with 500 ml. of cold water, cooled, and the precipitated yellow solid collected and dried. Recrystallization from 50% aqueous ethanol give the pure compound melting at 154155 C.

EXAMPLE 28 Preparation of 2-(2-Piperidino-5-thiadiazolyl)-1-methyl- 5-nitroimidaz0le A mixture composed of 7.4 g. of 2-(2-chloro-5-thiadiazolyl)-1-methyl-5-nitroimidazole (Example 16), 6 g. of piperidine, and 200 ml. of dioxane is stirred at room temperature for 24 hours, and then taken to dryness under reduced pressure. The residue is shaken with ml. of water and the insoluble portion collected and dried. Recrystallization from 150 ml. of Z-methoxyethanol gives 7.6 g. of the subject compound melting at 212-213 C.

EXAMPLE 29 Preparation of 2-(Z-n-Hexylamino-S-thiadiazolyl)-1- methyl-S-nitroimidazole The preparation of the title compound is carried out es sentially as described for the 2-piperidino derivative (Example 28), 6.5 g. of n-hexylamine replacing the piperidine. The crude product is recrystallized from ml. of

2-methoxyethanol to give 5.2 g. of the pure compound melting at 146-147 C.

EXAMPLE 30 Preparation of 2- [4- 2-Hydroxyethyl) l-piperazinyl-S- tbiadiazolyl]-1-methyl-5-nitroimidazole The preparation of the subject compound is carried out essentially as described for the Z-piperidino derivative (Example 28), 3.9 g. of l-(2-hydroxyethyl)piperazine replacing the piperidine. After recrystallization from ethanol, 3.5 g. of pure compound is obtained, melting at 204-206 C.

EXAMPLE 3 1 Preparation of 2-{2 [4 (3 Dimethylaminopropyl)-1- piperidino]-5-thiadiazolyl}-l-methyl-S-nitroimidazole The preparation of the title compound is carried out by the procedure described for the Z-piperidino derivative (Example 28), 5.1 g. of 4(3dimethylaminopropyl) piperidine replacing the piperidine. Recrystallization from methanol gives 5.6 g. of pure product, melting at 174- 175 C.

EXAMPLE 32 Preparation of 2-{2-[N-(Z-HydroxyethyDmethylamino]- 5-thiadiazolyl}-l-methyl-S-nitroimidazole The preparation of the above compound is carried out essentially as described for the Z-piperidino derivative (Example 28), an equivalent of N-methylethanolamine replacing the piperidine. The pure compound melts at 158 -160 C. after recrystallization from methanol.

EXAMPLE 33 Preparation of 2- [2-( 1-'Piperazinyl) -5-thiadiazolyl] -1- methyl-S-nitroimidazole The preparation of the subject compound is carried out essentially as described for the Z-piperidino derivative (Example 28), two equivalents of piperazine replacing the piperidine. The crude product is recrystallized from 2- methoxyethanol to yield the pure compound melting at 240-241 C.

EXAMPLE 34 Preparation of 2- [2- (4-Methyl-1-piperazinyl) -5-thiadiazolyl] l-methyl-S-nitroimidazole The preparation of the above compound is carried out in the manner described for the 2-piperidino derivative (Example 28), an equivalent of l-methylpiperazine replacing the piperidine. The crude product is purified by recrystallization from Z-methoxyethanol and melts at 242244 C.

EXAMPLE 35 Preparation of 2-{2 [4 (3 Dimethylaminopropyl)-1- piperazinyl]-5-thiadiazolyl}-1-methyl-5-nitroimidazo1e Preparation of 2-{2-[4-(2-Pyridyl)-l-piperazinyl]-5- thiadiazolyl}-l-methyl-S-nitroimidazole The preparation of the above compound is carried out essentially as described for the 2-[4-(3-dimethylaminopropyl) 1 piperazinyl derivative] (Example 35), an

equivalent of 1-(2-pyridyl)piperazine replacing the 1-(3- dirnethylaminopropyl)piperazine. After recrystallization from Z-methoxyethanol, the pure compound melts at 280-282 C.

EXAMPLE 37 Preparation of 2{2-[4-(2-Thiazolyl) 1 piperazinyH-S- thiadiazolyl}-1-methyl-5 -nitroimidazole The preparation of the subject compound is carried out essentially as described for the 2-[4-(3-dimethylaminopropyl) 1 piperazinyl] derivative (Example 35 an equivalent of 1-(2-thiazolyl)piperazine replacing the 1-(3- dimethylaminopropyl)piperazine. After recrystallization from 2-methoxyethanol, the pure compound melts at 297- 300 C.

EXAMPLE 38 Preparation of 2-(2-Cyclohexylamino-S-thiadiazolyl)-1- methyl-S-nitroimidazole A mixture of 5.0 g. of 2-(2-chloro-5-thiadiazolyl)-1- methyl-S-nitroimidazole, 6.0 g. of cyclohexylamine and 125 ml. of dioxane is stirred at reflux until thin-layer chromatographic analysis indicates that the chloro intermediate is completely utilized. The dioxane is removed under reduced pressure and the residue triturated with aqueous sodium bicarbonate solution. Recrystallization from a mixture of ethylacetate and acetone yields the pure compound melting at 215217 C.

EXAMPLE 39 Preparation of 2- (2-l-Butylamino- 5 -t'hiadiazolyl) 1- methyl-S-nitroimidazole The preparation of the above compound is accomplished essentially by the procedure described for the 2- cyclohexylamino derivative (Example 38), an equivalent of t-butylamine replacing the cyclohexylamine. Recrystallization of the crude product from a mixture of ethyl acetate and acetone gives the pure compound melting at 249-251 C.

EXAMPLE 40 Preparation of 2-(2m-Octylamino-S-thiadiazolyl)-1- methyl-S-nitroimidazole The preparation of the above compound is carried out essentially as described for the 2-cyclohexylamino derivative (Example 38), an equivalent of n-octylamine replacing the cyclohexylamine. The crude product is purified by recrystallization from aqueous 2-methoxyethanol and then melts at l30132 C.

EXAMPLE 41 Preparation of 2-(2-Chloroacetamido-S-thiadiazolyl)-1- methyl-S-nitroimidazole Twenty grams of 2-(2-amino-5-thiadiazolyl)-1-methyl- S-nitroimidazole is added in portions to a solution of 60 g. of chloroacetic anhydride in 250 ml. of dioxane at C. The mixture is stirred at this temperature for three hours. After standing at room temperature, the mixture is filtered and precipitate washed vw'th diethyl ether and dried. Recrystallization from Z-methoxyethanol gives the pure compound, melting at 239-240 C. with decomposition.

EXAMPLE 42 Preparation of 2-(2-Morpholinoacetamido-5- thiadiazolyl)-l-methyl-S-nitroimidazole Six grams of 2 (2 chloroacetamido-S-thiadiazolyl) l-methyl-S-nitroimidazole (Example 41) is added to a solution of 4 grams of potassium iodide in 2 liters of anhydrous acetone, and the mixture then influxed for two hours. Potassium chloride precipitates from the solution. Four grams of morpholine is added and the mixture refluxed for seven hours. The solvent is removed in a stream of air. The residual solid is slurried with ml. of water,

15 filtered, and dried. Recrystallization from 300 ml. of boiling dioxane gives 3.8 g. of the title compound, melting at 250*252 C. with decomposition.

EXAMPLE 43 Preparation of 2-(2-Amino-5-thiazolyl)-1-propyl-5- nitroimidazole The procedure of Example 23, with the substitution of fl-(l-propyl nitro 2 imidazolyl)styrene for fl-(lethyl 5 nitro2-imidazolyl)styrene in the first step is utilized to prepare 2-(Z-amino-S-thiadiazolyl)-l-propyl-5- nitroimidazole, melting at 234.5-236 C.

EXAMPLE 44 Preparation of Chick Diet The following feed composition is employed in all the poultry experiments hereinafter set forth except where otherwise stated:

Percent Vitamin Pre-Mix 0.5 Trace Minerals 0.1 Sodium Chloride 0.3 Dicalcium Phosphate 1.2 Ground Limestone 0.5 Stabilized Fat 4 Dehydrated Alfalfa, 17% 2 Corn Gluten Meal, 41% 5 Menhaden Fish Meal, 60% 5 Soybean Oil Meal, 44% 30 Ground Yellow Corn, Fine To 100 The vitamin pre-mix in the above feed composition is prepared from the following formulation. The expressions of quantity relate to units per kilogram of the feed composition.

Butylated Hydroxy Toulene mg 125 dl-Methione mg 500 Vitamin A I.U 3300 Vitamin D I.U 1100 Riboflavin mg 4.4 Vitamin E I.U 2.2 Niacin mg 27.5 Pantothenic Acid mg 8.8 Chloine Chloride mg. 500 Folic Acid mg 1.43 Menadione Sodium Bisulfate mg 1.1 Menadione Sodium Bisulfate mg 1.1 Vitamin B mcg 11 Ground Yellow Corn, Fine gm to 5 EXAMPLE 45 Utilization of Compounds of the Present Invention in Controlling Colibacillosis This example demonstrates the effectiveness of 2-(2- amino 5 thiadiazolyl) 1 methyl-S-nitroimidazole, 2- (Z-acetamido 5 thiadiazolyl)-l-methyl-S-nitromidazole, and other imidazoles in controlling colibacillosis in poultry.

Three groups of five-day old sex-linked pullet chicks are infected parenterally, in the left thoracic air sac, with 0.2 ml. of a 10- dilution of a T rypticase Soy Broth culture of Escherichia coli, the causative agent of colibacillosis in poultry. The compounds to be tested are administered by gavage as a single oral dose in an aqueous solution or suspension, and the chicks are permitted to feed composition prepared in Example 44. Twelve days after treatment, the test is terminated and the number of survivors in each group recorded. The results are compared With two control groups of chicks each, in which one control group, is infected and untreated, and the sec- 1 6 0nd control group is uninfected and untreated. The results of the test are set forth in the following table:

1 Dose is in terms of milligrams per kilogram of body weight.

F our groups of 40, five-day old sex-linked pullet chicks are infected in the same manner as herein set forth with Escherichia coli. The compound 2-(2-acetamido-5-thiadiazolyl)-1-methyl-5-nitroimidazole is administered by gavage as a single oral dose in an aqueous medium, and the chicks are permitted to feed ad libitum the feed composition prepared in Example 44. Twelve days after treatment, the test is terminated and the number of survivors in each group recorded. The results are compared with two control groups of 40 chicks each, in which one control group is infected and untreated, and the second control group is uninfected and untreated. The results of the test are set forth in the following table.

1 Dose is in terms of milligrams per kilogram of body weight.

EXAMPLE 46 Utilization of Compounds of the Present Invention in Controlling Fowl Typhoid This example demonstrates the effectiveness of the compounds of this invention.

Groups of five one-day old sex-linked pullet chicks are infected orally by gavage with 0.5 ml. of a 10 dilution of a five-hour Trypticase Soy Broth culture of Salmonella gallinarum, the causative agent of fowl typhoid. Each chick receives approximately 6x10 viable cells. Medication is administered continuously in the feed, beginning 3 hours before infection and continuing for 10 days, at which time the test is terminated and the number of survivors in each group recorded. Each test utilizes two control groups of chicks, the first group comprising 20 chicks which are infected and untreated, and the second group comprising 10 chicks which are uninfected and untreated. The results of the tests are set forth in the following Table III (in some instances, the results from two or more tests are TABLE III-Continued Total Dose, chicks Sur- Compound percent tested vivors 2-(Z-amino-S-thiadiazolyl)-1-ethyl5- nitroimidazole 0. 1 10 10 0. 025 10 9 2-(2-aniino-5oxadiazolyl)-1-ethyl-5- nitroimidazole 0. l 10 10 0. 025 5 5 006 3 2-(2-amino-5-thiadiazolyl)-1-benzyl-5- nitroimidazole 0. 1 10 0. 025 10 4 2-(2-amino-5-oxadiazolyl)-1-benzyl-5- nitroimidazole 0. 1 10 9 0. 025 10 1 0. 006 10 1 2-(2-hydroxymethylamino-Sthiadiazolyl)- l-methyl-fi-nitroimidazole 0. 1 10 10 O. 025 10 2 0. 006 10 2 2-{ 2-[N- (Z-hydroxyethyl) methylamino]-5- thiadiazolyl l-l-methyl-5-nitroimi dazole. 0. 1 10 8 2-(2-Morpholino-acetamido-fi-thiadiazolyl)- 1-methyl-5nitroimidazole 0. 1 10 1O 0. 025 5 1 2-(2-Amjno-5-thiadiazolyl)-1-methyl-5- nitroimidazole hydrochloride 1. 0 10 10 0. 025 5 3 2-[2-(4Methyl-1-piperazinyl)-5-thiadiazo1yl]-1-methyl-5-nitroimidazole 0. 1 10 4 2-(2-Ethylamino-S-thiadiazolyl)-1-methyl-5- nitroimidazole 0. 1 10 10 0. 025 I0 3 0. 006 5 3 2-(2-cyclohexylamino-5-thiadiazolyl)-1- methyl-fi-nitroimidazole 0. 1 10 8 2-(2t-butylamino-5-thiadiazolyD-l-methyl- 5-nitroimidazole 0. 1 10 6 2-(2-n-hexylarnino-5-thiadiazolyl)-1-methylfi-nitroimidazole 0. 1 10 6 2-(2-piperidino 5-thiadiazolyl)-1-methyl-5- nitroimidazole 0. 1 10 4 2-[2-(1-piperazinyl)-5-thiadiazolyl1-1- methyl-5-nitroimidazole 0. 1 10 8 0. 025 10 1 2-(2-amino-5-thiadiazolyl)-1-(Z-hydroxyethyl)-5-nitroimidazole 0. 1 10 10 0. 025 10 8 2-[4-(2-hydrox ethyl)-1-piperazinyl-5- thiadiazolyl -1-methyl-5-nitroiimdazole 0. 1 10 7 0. 025 10 3 2-(2dichloroacetamido-E-thiadiazolyl)-1- methyl-fi-nitroimidazole 0. 1 10 7 9. 025 3 2-l2-[(dimethylaminomethylene)axnino1-5- thiadiazolyl l-1-methyl-5-nitroimidazole- 0. 1 5 5 0. 05 5 5 2-(Z-Iormamido-S-thiadiazolyl)-1-methyl-5- nitroimidazole 0. 1 10 5 0. 025 15 11 0. 006 15 9 2-(2-amino-5-oxadiazolyl)-1-methyl-5- nitroimidazole 0. 1 10 10 0. 025 10 10 0. 006 10 9 2-(2-dimethylznnino-5-oxadlazolyD-1- methylfi-nitroimidazole 0. 1 10 9 0. 025 10 9 0. 006 10 2 2-(2-acetan1ido-fi-oxndiazolyl)-1-methyl-5- nitroimidazole 0. 1 10 1 0. 025 10 8 2-(2-methylamino-5-oxadiazolyl)-1-methyl- 5-nitro'nnidazole 0. 1 5 5 0. 025 10 10 0. 006 10 8 2-(2-methylamino-5-oxadiazolyl)-1-(2- hydroxyethyl)-5-nitroimidazole O. 1 10 6 2-(2-dimethylamino-5-oxadiazo1yl)-1-(2- hydroxyethyl)-5-nitroimidazole 0. 1 10 5 0. 025 10 2 -(2-aI11ino-5-thiadiazoly1)-1-propyl-5 nitroimidazole O. 1 10 6 Control:

Infected, untreated 0 Uniufected, untreated 1O 10 1 Dose is in terms of percentage by weight of the feed composition pre pared in Example 45.

1 8 EXAMPLE 47 Utilization of Composition of the Present Invention in Controlling Enteritis This example demonstrates the effectiveness of 2-(2 amino-S-thiadiazolyl)-1-methyl and l-ethyl-S-nitroimidazole in controlling enteritis.

Three groups of ten female Swiss Webster mice weighing 20 gm. are infected intraperitoneally with 0.5 ml. of 1O dilution of a five-hour Trypticase Soy Broth culture of Salmonella choleraesuis var. kunzendorf, the causative agent of enteritis in pigs, an organism originally recovered from a field outbreak of Salmonella choleraesuis var. kunzendorf in pigs. Each mouse receives approximately 4.6)(10 cells as the inoculating dose.

The mice are fed a medicated feed, which is a commercial mouse chow containing the compounds to be tested for 3 hours before infection until 7 days after infection. The mice are held for an additional 7 days after the medication is stopped, and the number of survivors in each group recorded. The medicated feed is prepared by thoroughly admixing calculated amounts of the compounds with commercial mouse chow to provide essentially uniform distribution in the feed offered. The above results are compared with two control groups of ten mice each, in which one control group is infected and untreated, and the second control group is uninfected and untreated. The results of the test are set forth in the following table:

h Dose is in terms of percentage by weight of the commercial mouse 0 ow.

EXAMPLE 48 Experiments were conducted to determine the antibacterial activity of compounds of the present invention against Proteus mirabilis, Staphylococcus aureus strain Smith and Staphylococcus aureus strain Rose a tetracycline-resistant strain of Staphylococcus aureus. Infection was initiated in Carworth Farms CFl-s female mice (body weight 18-22 mg.) by intra-abdorninal infection of 0.5 ml. of the broth dilutions of 5 hour cultures of the above organisms. The results obtained are summarized in the following Tables V, VI, and VII.

TABLE V Tests with Proteus mirabilis Results Dose, alive Compound mgJkg. tested 2-(2-amino-5thiadiazolyl)-1-methy1-5-nitroimida- 7019 128 30/30 2-(Z-methylamino-5-thiazoly1)-1-methyl-5- nitroimidazole 256 4/5 2-12-[(dimethylamino-methylene)amino]5-th1adiazolyl}-l-methyl-5-n.itroimidazole 256 3/5 2-(2-iormamido-5-thiadiazolyl)-1-methyl-5- njtmimi damle 128 20/ 20 2-(2-amino-5-thiadiazolyl)-1-methyl-5-nitroimidazole hydrochloride 128 7/10 TABLE VI Tests with Staphylococcus aureus stiain Smith Results Dose, alive/ Compound mgJkg. tested 2-(2-amino-5-thiadiazolyl)-1-methyl-5-nitroimidazole 64 16/20 Z-(Z-methylamino-S-thiadiazolyl)-1-methyl-5 nitroimidazole--. 128 4/5 2-[2-(4-carbethoxy-1 iperazinyl)-5-thiad1azolyl1-1- methyl-.S-nitroimidazolo 256 8/10 2-(2-diniethylamino-5-thiad zo hylnitroimidazole- 512 4/5 2-l2-(ldimethylami et 8);;

diazolyl-1-methyl-5-nitroimidazole. 64 5/5 2-(2tormamido-5-thiadiazo1yl)-1-meth nitroimidazole. 64 5/5 2-(2-amino-5-oxad nitroimidazole.-- 128 9/10 2-(2-acetamid0-5-ox nitroimidazole 128 3/5 2-(2-methylamino-5'oxadiazolyD-l-methyl nitroimirhmln 128 3/5 2-(2-amino-5'oxadiazo1yl)-l-ethyl-5-nitroimidazole 128 3/5 2-(2-andno-5-thiadiazolyl)-1-methyl-5-mtro1m1dazole hydrochloride 128 5/5 2-l2-[4-(3-dimethylaminopropyl)-1-p1perazmyl]-5 thiadiazolyll-1-methyl-5 nitroim1dazole 256 3/5 The mortality among infected untreated controls in this test is usually at least 95% TABLE VII Tests with Staphylococcus aurcus strain Rose Results Dose, alive] Compound mgJkg. tested 2-(2-amino-5-thiadiazoly) -1-methyl-5-nitroimidaz ole- 128 10/ 10 2-(2-methylamino5-thiadjazolyl)-1-methy1-5-nitroimidazole 512 4/5 2-( 2-] (dimethylaminomethylene) amino] -5-thiadiazolyl l-1-methyl-5-uitroimidazole 128 10/ 10 2-(2-formamido-5-thiadiazolyl) -1-methyl-5-mtro inu'dazole 512 5/5 2-(2-amino-5cxadiazolyl)-1-methyl-5-nitroimidazo1e 512 5/5 2(2-dim0thylamino5-oxadiazoly) -1-methy1-5- nitroimidazole. 512 5/5 2-(2-methylamino imidazole 128 5/5 2-(2-amino5-thiadiezolyl)-1-ethyl-5-1ntr01m1dazole- 512 5/5 2-(2-ami no-5oxadiazolyl) -1-ethyl-5-nitroimidazole 512 5/ 5 The mortality among infected untreated controls in this test is usually 95% or more. Activity was also displayed by the compounds of this invention against the following organisms in mice: E. coli, Salmonella typhosa, Klebsiella AD, Aerobacter aerogenes, and Streptococcus pyogenes strain A (C 203).

EXAMPLE 49 This Example Demonstrates the Effectiveness of the Nitroimidazoles of This Invention in Controlling a Pasreurella Multocida Infection in Mice Swiss Webster, female mice weighing 22:2 g. were infected by intraperitoneal injection of 0.5 ml. of a 5 hour Trypticase Soy Broth culture containing 10" cfu. of P. multocida. Each mouse was given by gavage at the time of infection 2 mg. of the test drug suspended in 0.2% agar. The number of mice surviving two weeks post-infection over the number of mice tested is recorded below for each compound. The results are shown in Table VIII.

TABLE VIII MgJmouse Compound Survivors/total 2(2-a.mino-5-thiadiazolyl)-1-etl1yl- 5-nitroimidazole 10/10 2-(2-amino-5-oxadiazolyl)-1-ethyl- 2 fi-nitroimidazole 8/10 -(2-nmiuo-5thiadiazolyl)-1-beuzyl- 5-nitroimidazol0 /10 Z(Z-hydroxymothylarnino--thiadiazolyl)-l-methyl-5-nitroimidazole 10/10 Z-l 2-lN -(2-l1 ydroxyethyD-lneth yl- 5-njtroimidazole 10/10 3/10 1/10 2'(2-morpholinoaeetamido-5- thiadiazolyD-l-methyl-5- nitroimidazole 2/10 Compound 2-(2'ethylamino-5-thiadiazolyl) -l methyl-S-nitroimidazole 2-l 2-[4-(S-dimethyla1nin0propyl)- l-piperazinyl]5-thiadiaz0lyl l -1- methyl-5-nitroimidazole 2-(2-n-hexylamino-5-thiadiazolyl) 1-methyl5-nitroimidazole 2- (Z-piporidino-S-th iadiazolyl) 1 metlryl-nitroimidazole 2-(2-arni no-5-oxadiazolyl) -1- (2- hydroxyethyl) '5-nitr0imidaz0le 2( 2-[4-(2-thiazolyl)-1-piperazinyl1- S-thiadiazolyl -1-rnethyl-5- nitroimidazole 2-[2- (l-piperaziny 5 l-methyl-B-nitroimrdazole 2- [4- (2-hydroxyethyl) -lpiperazinyl- 5thiadi azolyl] -l-rneth yl-5- nitroimidazole 2-l 2-[4- (3-dimethylaminopropyl) -1- piperidjno]-5-thiadiazolyl} -1- methyl-fi-nitroimidazole 2- (Z-aminO-S-thiadiazolyl) -1- methyl-initroimidazole 2-l 2-[(din1eth ylaminomethylene) ami no] -5-thiadiazolyl -1-methyl- 5-nitroimidazole 2- (2-tormamido-5-thi adiazolyl) -l methyl-5nitroimidazole 10/ 10 2-(aminoo-thindiazolyl)-1-(2- hydroxyethyl)'5 nitroimidazole 2- (2-amin0'5-oxadiazolyl) -1-n1ethyl- 5-nitroimidazole 14/20 EXAMPLE 50 This example demonstrates the effectiveness of 2-(2 amino-S-thiadiazolyl)-l-rnethyl-S-nitroimidazole in controlling enteritis caused by Salmonella choleraesuis in swine.

In the late afternoon of the day before infection, feed is removed from all pens. The following morning each group receives 25 lbs. of feed mixed either with normal broth or broth containing Salmonella choleraesuis variety kunzendorf organisms. Most of this feed is consumed within an hour. For the rest of the trial the pigs are observed and graded daily. Five hours after infection the pigs are given normal feed or feed containing furazolidone, a known antisalmonella agent, or 2-(2(-amino-5- thiadiazolyl -1-methyl-5-nitroimidazole. Medicated feed is employed for 14 days after infection, at which time it is replaced with normal feed. The trial is terminated four weeks after infection. The results of this experiment are shown in Table IX. I

TABLE IX Mortality of pigs infected via feed with Salmonella Cholcrncauis var. kunzemlorf and medicated via feed for the first 14 post-infection days During first day postinfeetion. Differs significantly from infected, untreated group (P .01).

EXAMPLE 51 The compound 2-(Z-amino-S-thiadiazolyl)-1-methyl-5- nitroimidazole (Example 1) is active against both gramnegative and gram-positive organisms. In mice, it is rapidly absorbed, well tolerated and effective against lethal bacterial infections. In vitro, it is effective against gonococci and gram-negative bacilli. Its action is bactericidal.

In the following experiments both the base and the hydrochloride salt of 2-(2-amino-5-thiadiazolyl)-1-methyl-5- nitroimidazole are used. On a molar basis, they are equivalent in activity. In mice, the method used in this experiment has been described. (Redin, G. S., Antibacterial Activity in Mice of Minocyclin, a New Tetracycline, Antimicrobial Agents and Chemotherapy1966, pp. 371- 376). Infections are initiated in Carworth Farms CF-l female mice (body weight, 18 to 22 g.) by intra-abdominal injection of 0.5 ml. of the indicated broth dilutions of -hour cultures of the following organisms: Klebsiella pneumoniae AD, Salmonella typhosa 6539, undiluted; Escherichia coli UC311, 10 Aerobacter aerogenes 75, 10- Proteus mirabilis 4671, 10- Shigella flexneri 2a M22 18, undiluted; Stn'eptococcus pyogenes C203, 10- Staphylococus aureus 3, undiluted; S. aureus Rose, undiluted; S. aureus 5, undiluted; S. aureus Smith, 10-2; and Diplococcus pneumoniae SVI, 10*. For the Neisseria meningitidis N infection, 0.5 ml. of a 48-hour broth culture is used. Within 1 hour after infection, the mice are treated with drug suspended in 0.5 ml. of 0.2% aqueous agar administered by oral gavage. The drugs are tested at four to six dosage levels with 20 to mice at each level. The results of replicate tests are pooled to determine the median effective dose (ED by the procedure of Litchfield and Wilcoxon, 1949, a simplified method of evaluating dose-effect experiments, I. Pharmacol. Exptl. Therap. 96299-113. Data are given in Table X hereinafter.

TABLE X The compound 2-(Z-amino-S-thiadiazolyl)-1-methyl-5-nitroimidazole tested against bacterial infections in mice (single oral dose) Median effective dose Shigella flexneri 2a M22-18 89 52-150 Streptococcus pyogenes C203 4 (3-6) Staphylococcus aureus 3 14 (9-21) S. aureus Rose 28 (18-44) S. aureus 5 46 (26-81) S. aureus Smith 56 (40-77) Diplococcus pneumoniae SV1 69 (53-90) 3 Mortality rate of the untreated infected control mice was 90% within 3 days. The experimental period was 14 days. Figures in parentheses indicate 95% confidence limits.

Concentration of drug in plasma are determined by assay of blood obtained by heart puncture of noninfected mice. Blood samples (about 0.5 ml. per mouse) from 10 mice receiving the same dose of drug are pooled. The drug is assayed in the plasma by a standard agar-diffusion plate method with Bacillus subtilis (Lederle No. 17) as the test organism. Peak plasma drug concentrations are given in Table XI hereinafter where they are associated with the median elfective dose.

TABLE XI Peak concentrations of test compound in plasma associated with median ettective doses 1 Peak con EDso in plasm Infection (mg/kg.) gJmlfi;

Neisseria meningitidis N20 Streptococcus pyogenes C203 Klebsz'ella pneumoniae AD Salmonella typhosa 6539 Escherichia coli 811 Staphylococcus aureus 3 Staphylococcus aureas Rose Staphylococcus aureus 5 Staphylococcus aureus Smit 22 EXAMPLE 52 The following organisms are used in an in vitro testing study involving the following species: Neisseria gonorrrhoeae (3 6 strains), N. meningitidis (24), Shigella flexneri (II), S. sonnei (3), Salmonella typhimurium (5), S. enteriditis (1), S. infantis (1), S. cholerasuis (1), S. organienburg (1), Salmonella species not further identified (5), E. coli (24), Enterobacter (21 strains of Klebisella pneumoniae and Aerobacter aerogenes), Proteus sp., all indole-negativc (20), Pseudomonas sp. (10), D. pneumoniae (10), Streptococcus pyrogenes (15), Staphylococcus aureus (23), Streptococcus faecalis, enterococci (28). The media used are Nutrient Broth (Difco), Nutrient Agar, Nutrient Agar containing 5% defibrinated rabbit blood, or chocolate agar prepared by combining the following materials from BBL; GC medium base, hemoglobin, and enrichment supplement.

The efiectiveness of the antibacterial agents against the clinical isolates is determined by the agar-dilution method. 2-(2-amino 5 thiadiazolyl)-1-methyl-5-nitroimidazole is relatively insoluble in water; therefore, a stock solution is prepared in dirnethylsulfoxide (DMSO) and serially diluted in DMSO, then 0.1 ml. of dilution is mixed with 10 ml. of fluid agar. The concentration (1%) of DMSO did not affect the growth of the test cultures. The plates are inoculated with 10" dilutions of 5 hour broth cultures by means of a multiple inocula-replicator. (Steers, E., E. L. Foltz, and B. S. Graves, An inocula Replicating Apparatus for Routine Testing of Bacterial Susceptibility to Antibiotics, Antibiot. Chemotherapy 9: 308-311 (1959). With meningococci and gonococci, 24- to 48-hour surface growth on chocolate agar is suspended in Trypticase Soy Broth (BBL) for reading of 40 to 50% transmittance at 530 nm in a Bausch and Lomb Spectronic-ZO colorimeter; the cultures are then diluted 1,000- fold in broth. Inoculated plates are incubated at 37 C. for 24 hours; meningococci and gonococci are incubated in an atmosphere of 5% carbon dioxide. The lowest concentration of drug that completely inhibited growth is recorded as the minimal inhibitory concentration.

For the comparison of inhibitory and killing concentrations, tests are performed in Nutrient Broth. A stock solution of the test compound in DMSO (5,120 ag/ml.) is diluted 1:40 in broth and sterilized by filtration through a 0.2- m. membrane filter (Millipore Corp., Bedford, Mass). T wofold dilutions of the sterile broth solution are inoculated with equal volumes of 10* dilutions of a 5- hour broth culture and are incubated at 37 C. for 24 hours. Subcultures are made from all clear tubes by plating 0.1-ml. samples in duplicate and incubating the plates for 124 hours. The following Table XII summarizes the resu ts.

TABLE XII Activity of 2-(2-armno-5-thiadiazolyl)-1-mothyl-5-nitroimidazole clinical isolates (agar-dilution method) Number of isolates Test Organism tested compound a Gonococcus- 36 0. 12 Menincococcus 24 1 Shigella. 14 4 Salmonella 14 4 E. coli 24 8 Enterobacter 21 8 Proteus 2O 64 Pseudomonas..- l0 128 Diplococcus 10 4 Streptococcus Group A 15 8 Staphylococcus 23 16 Enterococcus 28 64 Drug concentration g/ml.) required to inhibit 0! isolates.

EXAMPLE 53 The efiicacy of the compounds of the present invention for enhancing the growth rate and for improving feed efficiency of animals is shown in the following tests. Dayold chicks are divided into groups of ten birds each, five males and five females. These groups are then weighed,

23 placed in pens and given free access to water and feed. The diet used is the same for both the test groups and the controls except that 100 p.p.m. of Z-(Z-amino-S-thia- 24 p.p.m. of test compound was included in the diets of test groups.

Data obtained are reported in Table XIV below.

TABLE XIV Day Percent increase l9 Gain, Lb. over controls Number 10 iced/lb. Supplement birds Weight in grams days gain Gain F/G No Q 10 40.5 323.5 283. 0 1.57 2-(2-amlno-5- 10 40. 6 339. 7 299. 1 1. 47 6. O 6. 8 None 10 41. 9 332. 0 200. 1 1. 52 2-(1- ethyl-5-nitro-2-imiclazolyl)-5piperidino-1,3,+

thladiazole 1O 42. 0 334. 7 292. 7 1. 48 1. O 2, 7

None 42. 4 324. 6 282. 5 1. 53 10 43. 7 322. 2 278. 5 1. 53

1-[5-(l-methyl-5-nlt1'0-2-imidazolyl)-1,3,4-tl1iadiazol-2- yl]-4-(2-thiazolyl)piperazine 0 42. 3 337. 8 315. 5 1. 47 5. 0 4. 1 10 43. 7 346. 9 303. 2 1. 50 9. 0 2. 0

None .1 10 40. 4 344. 6 304. 2 1. 58 N- 5- 1-(2-hydroxyethyl)-5-nitro-2-imidazolyl -1,3,4-

tliia dlazo1-2-yl]-acetam1de 0 40. 4 345. 9 a. 5 1. 57 O. 7 0. 6

diazolyl)-1- (2-hydroxyethyl)-5-nitroimidazole is admixed EXAMPLE 5 5 with the diet of the test groups. All feed is weighed such that an accurate determination as to the amount of gain per unit of feed can be ascertained.

All groups are Weighed at 0 and 19 days after the test is begun and the data obtained are reported below. Table XIII, along with a description of the diet used.

TABLE XIII Days Percent increase 0 19 over controls Number Gain, Lb. feed] Supplement birds Wt. in grams 19 days lb. gain Gain FIG Average 43. 1 318. 7 276 100 p.p.m. 2-(2-amiligoi5-thiadiai l zi z l y Hmm' 10 43 352.2 300 Do 9 43. 2 327.8 235 Average 43. 1 340 297 DIET r approximately 4 weeks of age and placed on test imme- 00 diately. The following experimental treatments are used: Ingredient Concentration (percent) A Basal (Unmedicated ration) Ground yellow com B. -Basal-|-Compound X gmjton of f d) Soy an oil m (44%) 0.0 C. Basal-l-Compound X (100 m/ton of f d) Corn gluten meal 5.0 55 +C p u d X (200 gin/ton of feed) Menhaden fi t l 0% 5 'BaSa1+AuT60u (5.1- 250 (1 00 gm. of cholestetracy- 4 0 cl1ne, 100 gm. of sulfamethazine and 50 gm. of pencil- Fat g; l'f 7}; 2'0 lin/ton of feed).

1 Dehydrmfd a a a 2 0) O 5 Compound X:2-(Z-ammo-S-ttnadrazolyl)-1-methyl-5-mf lmestone 0 troimidazole Dlcalcmm phosphate 12' The composition Of the basal ration fed is show i Sodium chloride 0.3 Table XV. The length of these experiments is 42 days. Trace minerals 1 0,1 u s vitamin premixz 05 The average performance data for these two experiments is shown in Table XV. The daily gains for all three Lime Crest Z-2 Delamix which contains 25.5% calcium, 0.0% manganese, 2.0% iron, 2.0% Zinc, 0.12% iodine and 0.02% cobalt.

-Provides 3300 LU. Vitamin A, 1100 LU. Vitamin 1):}, 2.2 I.U. Vitamin E, 500 mg. choline chloride, 500 mg., DL- methionine, 125 mg. ethoxyquin, 27.5 mg. niacin, 8.8 mg. pantothenic acid, 4.4 mg. riboflavin. 1.43 mg, folic acid, 1.1 mg. menadione, 0.011 mg. Vitamin B12 per kilogram of feed.

EXAMPLE 54 In the following tests, the same diet and procedure were used as described in Example 53 above, excepting that 10 levels of 2-(Z-amino-S-thiadiazolyl)-l-rnethyl-S-nitroimidazole are clearly superior to those for the unmedicated control pigs. The pigs receiving the two higher levels and 200 grams per ton) gained more rapidly than those receiving the lower level (50 gm./ton). Treatment E (Aureo SP. 250) is included in these experiments as a positive control.

A marked improvement in feed efiiciency was obtained at all levels of 2-(Z-amino-S-thiadiazolyl)-1-methyl-5-nitroimidazole fed.

25 TABLE XV Basal swine ration Ingredient Percent Ground yellow corn 55.5

Soybean oil meal (44% protein) 17.5

Rolled oats 10.0

Sugar 5.0

Dried skim milk 5.0

Dried whey 2.5 Fish meal 2.5

Dicalcium phosphate 1.5

Iodized salt 0.5

Total 100.0 1 Trace minerals 1 a Vitamins TABLE XVI Average performance data for young pigs fed several levels of 2 (2-amino- 5-thiadiazolyl)-1-methyl-5-nitroimidazaole in the feed for 42 days A B o D E Compound X (gm./ton) Aureo S.P. Control 50 100 200 250 Number pigs started:

Experiment:

Total 24 24 24 24 Morztality: t

xpnmen r 1 2 0 0 1 0 2 3 1 0 1 1 Total 5 1 0 2 1 Average initial wt.,

lbSJ

Experiment:

Average l6. 0 15. 8 0 16. 1 16. 2

Average daily gain lbs.:

Experiment:

Average 54 62 74 74 66 Average feed/gain ratio: 50

Experiment:

Average 2. 84 2. 51 2. 38 2. 40 2. 56

EXAMPLE 56 After thoroughly mixing the above phase in 12 hard gelatin capsules. lEach capsule will contain 40 mg. of active drug.

EXAMPLE 57 Ingredients Amount, mg.

2-(2-methy1amino-5 thiadiazolyl) methyl-5- nitroimidazole 600 Lactose 1000 Mix thoroughly and place in 6 hard gelatin capsules. Each capsule contains mg. of drug.

We claim:

1. A method for enhancing the growth rate of warmblooded animals which comprises administering to said animals a growth promoting amount of 2-(2-amino-5- thiadiazolyl)-1-methyl-5-nitroirnidazole.

2. A method for enhancing the growth rate of warmblooded animals which comprises administering to said animals a growth promoting amount of 2-(2-amino-5- thiadiazolyl) -1-( Z-hydroxyethyl) -5-nitroimidazole.

3. A method for enhancing the growth rate of warmblooded animals which comprises administering to said animals a growth promoting amount of N-[5-[1-(2- hydroxyethyl)-5-nitro-2-imidazolyl]-1,3,4thiadiazo1e 2- yl] acetamide.

References Cited UNITED STATES PATENTS VINCENT D. TURNER, Primary Examiner US. Cl. X.R. 424-250, 267 

